Machine for wrapping continuous cores in tape material

ABSTRACT

A machine for wrapping continuous cores in tape material intended preferably for manufacturing V-belt blanks is disclosed, said machine comprising a mechanism for spiral-pattern wrapping of a core in material having a gear with a radial slot and rotated through a pair of idle gears. Secured to this gear at an angle to its axis of rotation is a holder for a reel wound with tape material. The above-mentioned gear is mounted on a hollow axle fixed to a carriage which is installed with a possibility for setting displacement along the bedframe in relation to the driving pulley. The hollow axle has a longitudinal cut which coincides with the radial slot made in the gear, whereas one of the branches of a core tensioned by the driving and driven pulleys is inserted through the slot and the cut into the hollow of the axle. The proposed machine permits wrapping a core of any size and cross-sectional profile with a required number of wrapping layers during a single revolution and with no folds or overlaps to occur.

United States Patent [191 Polshikov et a1.

[451 Dec. 10,1974

[ MACHINE FOR WRAPPING CONTINUOUS CORES IN TAPE MATERIAL [76] Inventors: Ivan Vasilievich Polshikov, ulitsa Parkovaga, 10, kv. 5, Kursk; Lev Nikolaevich Kurdin, ulitsa Pervomaiskaya, 90, kv. 57', Alexandr Timoteevich Titarenko, Poselok NIIRP, 2, kv. 77, both of Moskovskaya Oblast, all of USSR.

22 Filed: Oct. 25, 1972 21 Appl. No.: 301,257

I [52] U.S. Cl 156/422, 156/428, 156/460, 242/41 R [51] Int. Cl B29h l7//32 [58] Field of Search 156/425-432, 156/422, 460; 242/4 B, 4 BE, 4 C, 6, 7.19

[56] References Cited UNITED STATES PATENTS 1,132,359 3/1915 Kremer 156/422 X 1,582,026 4/I926 Duclos 156/432 X 1,935,239 11/1933 Denny 242/6 X 3,448,506 6/1969 Bishop et al..... 242/7.l9 X 3,718,523 2/1973 Mallory et a1. 156/460 FOREIGN PATENTS OR APPLICATIONS 303,609 l/1929 Great Britain 156/422 v 521,955 6/1940 Great Britain 156/422 104,628 7/1938 Australia ..156/460 Primary Examiner-Douglas J. Drummond Assistant Examiner-David A. Simmons Attorney, Agent, or Firm-Holman & Stern [5 7 ABSTRACT A machine for wrapping continuous cores in tape material intended preferably for manufacturing V-belt blanks is disclosed, said machine comprising a mechanism for spiral-pattern wrapping of a core in material having a gear with a radial slot and rotated through a pair of idle gears. Secured to this gear at an angle to its axis of rotation is a holder for a reel Wound with tape material. The above-mentioned gear is mounted on a hollow axle fixed to a carriage which is installed with a possibility for setting displacement along the bedframe in relation to the driving pulley. The hollow axle has a longitudinal out which coincides with the radial slot made in the gear, whereas one of the branches of a core tensioned by the driving and driven pulleys is inserted through the slot and the cut into the hollow of the axle.

The proposed machine permits wrapping a core of any size and cross-sectional profile with a required number of wrapping layers during a single :revolution and with no folds or overlaps to occur.

4 Claims, 7 Drawing Figures PATENTEB DEC 1 [H974 SHEEE E U? Q MACHINE FOR WRAPPING CONTINUOUS CORES IN TAPE MATERIAL BACKGROUND OF THE INVENTION The present invention relates to machines for wrapping continuous cores in tape material and can be widely employed at plants producing industrial rubber goods.

Known at the present time are machines for wrapping continuous cores in tape material manufactured by the Pirelli company of Italy.

These machines incorporate a driving and a driven pulleys for tensioning and moving the cores, a driven pulley tension mechanism and a mechanism for wrap ping a core in tape material, having a holder for a reel wound with tape material.

In these machines, the holder with a reel is immovable and the material is unwound manually or due to the motion of a core when the tape is stuck thereto. The mechanism for wrapping a core consists of a system of rollers and two horizontal rotatable sprockets ensuring lapping of the ends of tapes either on the lower or on the upper base of the core after the latter is preliminarily turned on the pulleys. This results in a core having a longitudinal scallop consisting of two lay ers of cloth if the core is wrapped in a single layer, and of four layers with two-layer wrapping, etc, but if lateral joints are made the number of layers in a scallop may reach six and more.

Joints of the wrapping material wound in an overlapped manner make a belt more rigid and present concentrations of stresses generated during operation of the belt which may cause cracks both in wrapping lay ers and in the core of a belt.

However, these machines do not permit wrapping a core in tape material in a spiral and overlapped pattern with displacement of tape turns because the holder of the reel wound with tape material is immovable and is not able to perform rotary motion around the core, while the wrapping mechanism is absolutely not suitable for spiral winding of tape material round the core.

Known in the present state of the art is a tire-making machine with wires placed in the edge of the tire side .by a method of spiral wrapping a tape from a rotating reel around two wires moving in the longitudinal direction and diverging on the driven pulley due to the grooves provided thereon (cr. German Patent No. 413,127, cl. B29h).

The above-said machine cannot be employed for wrapping cores of different profiles and with a various number of wrapping cloth layers, because the spiralpattem application of the tape is effected to a hollow fixed cylinder having a slot with a subsequent pulling off the cloth tape from the cylinder by means of two wires but not directly to the core being wrapped. Apartfrom that, the perimeter of the hollow cylinder is substantially larger than the perimeter of the core owing to which the cloth applied to the cylinder in a spiral pattern cannot be removed by the moving core.

In the given machine, it is practically impossible to locate one of the branches of a core at the center of the rotating gear because the slot in this gear is small and made within the limits of the module. There is practically no possibility to enlarge the size of the slot as this will disturb the rotation drive to the gear.

SUMMARY OF THE INVENTION It is therefore a general object of the present invention to provide a machine for wrapping continuous cores in tape material that would ensure wrapping a core in a spiral overlapped pattern with a required number of wrapping layers of tape material during a single revolution of the core on the pulleys.

This and other objects are achieved due to the provision of a machine for wrapping continuous cores in tape material, comprising a driving and a driven pulleys mounted on a bedframe for tensioning and moving a core, a driven pulley tension mechanism and a mechanism for spiral-pattern wrapping of a core in tape material, consisting of a rotatable gear having a radial slot and carrying on its end face at an angle to the axis of rotation a holder for a reel wound with tape material; whereas according to the invention, the machine is provided with a carriage installed with a possibility for setting displacement along the bedframe of the machine in relation to the driving pulley and. incorporating a hollow axle with a longitudinal cut to accommodate therein one of the branches of a tensioned core and to which the axle is fixed, said rotatable gear whose radial slot coincides with the cut of the axle when one of the branches of the core being inserted through them into the hollow of the axle, whereas the gear is put into rotation through the agency of at least one pair of idle gears spaced at a distance from each other in such a way that the distance between the points of tangency of their pitch circles is larger than the length of an arc of the slot made in the rotatable gear.

Positioning of the rotatable gear on the hollow axle of the carriage with a possibility for setting displacement in relation to the driving pulley is motivated bythe necessity to vary the distance between the driving pulley and the rotatable gear with a reel holder with a view to increasing rigidity of a turned section of the core which for different core profiles would be of different lengths.

The above-mentioned location of the idle gears makes it possible to provide a slot :in the rotatable gear with full account of the maximum height of the core cross section.

It is expedient that between the driving pulley and the carriage there be installed a mechanism for centering the core to the axis of gear rotation in the course of wrapping the core, said mechanism being fixed to the hollow axle of the carriage and made as two pairs of rollers installed in pairs close to each other in the horizontal and vertical planes, said rollers within each pair being so spaced and arranged that when in combination the pairs of rollers provide an opening whose geometrical dimensions correspond to the cross-sectional profile of the core wrapped in tape material, while one of the vertical rollers is imparted an ability for moving in the vertical plane to permit accommodation in said opening of one of the branches of the core tensioned on the pulleys.

This mechanism prevents any possibility of breaking the belt core under unfavorable wrapping conditions such as at high flexibility of the core, high cohesion between layers of wrapping tape on the rotating reel due to a high brake torque being put up by the reel.

For centering the .core to the axis of the rotatable gear when wrapping differently profiled cores, the driven and the driving pulleys should be provided with turning levers to move the pulleys in the vertical plane with a view of making the geometrical axis of the carriage hollow axle coinciding with'a neutral axis of the core when turned to ensure core wrapping free of folds or overlaps.

It is expedient that rotating speeds of the gear and the driving pulley be synchronized so that during a single revolution of the gear the driving pulley moves the core through pitch value equal to the perimeter of the turned core, otherwise it will be impossible to effect wrapping of the core in the required number of layers.

If the core has to be wrapped in several layers per single revolution thereof, a flexible arm may be installed at the point where the holder is secured to the gear, the free end of this arm being adapted for constant contact with the tape material unwinding off the reel. This arm will tension the loose half of the tape width applied as a first layer to the core, because the second half of this tape is applied to the core already increased in the perimeter by one layer of clotch in case the core wrapping is effected in two layers, etc.

' The proposed machine for wrapping continuous cores allows cores of any size and cross-sectional profile to be wrapped in a required number of wrapping layers per single revolution of the core. This yields a considerable increase in labor, productivity and improves the quality of wrapped cores due to the elimination of overlaps in the upper and lower bases of the core.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may be more clearly understood a specific embodiment of a machine for wrapping continuous cores in tape material will now be de scribed with reference to the accompanying drawings, in which:

FIG. 1 is a general view of a machine, according to the invention;

FIG. 2 is a schematic diagram of a drive for a rotatable gear of a machine;

FIG. 3 is a perspective view of a mechanism for centering a core;

FIG. 4 is a view in the direction of arrow A in FIG.

FIG. 5 is a plan view of a machine with a tension mechanism not shown;

FIG. 6 is a schematic diagram of a turning lever of a tension pulley of a machine; and

FIG. 7 is a schematic diagram of unit B shown in FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A machine for wrapping continuous cores, for example of V-belts, comprises a bedframe including a frame 1 (FIG. 1) which is connected through a fixed guide member 2 to a rear upright 3; a driving pulley 4 and a driven pulley 5 for tensioning and moving a core; a mechanism 6 for tensioning the driven pulley 5 and a mechanism 7 for spiral-pattern wrapping of a core in tape material.

The machine is provided with a carriage 8 which is installed with a possibility for setting displacement along the bedframe in relation to the driving. pulley 4. The mechanism 7 for spiral-pattern wrapping of a core incorporates a rotatable gear 9 having a radial slot 10.

Secured to the end face of the gear 9 (FIG. 1) at an angle of 45 to its axis of rotation is a holder 11 for a reel 12 wound with tape material.

The carriage 8 (FIG. 2) includes a hollow axle 13 having a longitudinal cut 14. Secured to the axle 13 is the gear 9. When the slot 10 and the cut 14 are made coinciding, one of the branches of a core tensioned round the pulleys 4 and 5 (FIG. 1) is inserted through the mentioned slot and cut into the hollow of the axle 13.

The gear 9 is driven for rotation through a pair of idle gears (not shown) or two pairs of idle gears 15 (FIG.2) driven from a shaft-gear 16.

In that pair of idle gears 15 which is in mesh with the gear 9, the gears 15 are so spaced that the distance L between the points of tangency C and D of pitch circles of the gears 15 and 9 is larger than the length of arc l of the slot 10 in the rotatable gear 9, which prevents the latter gear 9 from disengaging the idle gears 15 at the length of are 1 determined by an angle less than this meaning that the width of the slot 10 can be made with full account of the maximum height of belt cores to ensure free insertion of the cores into the hollow axle 13.

Installed between the driving pulley 4 (FIG. 1) and the carriage 8 is a mechanism for centering a core to the axis of rotation of the gear 9 in the course of wrapping a core. This mechanism is secured to the axle 13 (FIG. 3) of the carriage 8 and consists of two pairs 17 and 18 of rollers installed close to each other, whereas the pair 17 of rollers is installed in the horizontal plane, while the pair 18 of rollers is installed in the vertical plane. The rollers in each pair 17 and 18 are so spaced that when in combination the pairs of rollers are adapted to form an opening 19 (FIG. 4) whose geometrical dimensions correspond to the cross-sectional profile of a core wrapped in tape material.

One of the rollers included in the pair 18 installed in the vertical plane is adapted for displacement in the vertical plane with a view of allowing one of the core branches to be placed in or removed from the opening 19 when the latter one roller is lifted. To this aim, affixed to the hollow axle 13 (FIG. 3) is a bracket 20 having a hole 21 (FIG. 4) which houses a movable roller, and also three threaded holes 22 to fix the remaining three rollers therein. The movable roller included in the pair 18 is provided with a head 23 to retain the latter roller in the hole 21. Apart from that, the above roller is furnished with a freely rotating bushing 24 resting on a limit ring 25 which is affixed to the axle of this roller by a screw 26. A freely rotating bushing 24 reduces friction between the roller and the core.

For setting displacement of the carriage 8 (FIG. 5) the frame 1 has guide members 27 for the carriage to slide therealong, whereas the guide members 27 bear slots 28 to enclose bolts 29 for fixing the carriage 8.

Should a necessity arise for displacing the carriage 8 towards the driving pulley 4 or away from said pulley, the bolts 29 are unscrewed and the carriage 8 is displaced along the guide members 27 after which it is fixed in a new position by the bolts 29 seated in slots 28.

The mechanism 6 for tensioning the driven pulley 5 includes a pneumatic cylinder 30 (FIG. 1) having a rod 31 which is connected to a beam 32 movable within guide members 33, and a stop 34 positioned on a free end of the beam 32 and connected to the pulley 5.

For centering a belt core to the axis of the rotatable gear 9 during wrapping of differently profiled cores, the driven pulley 5 and the driving pulley 4 are fitted with turning levers 35 and 36 respectively.

The turning lever 35 is affixed to an axle 37 (FIG. 6) mounted on a stop 34. One end of the lever 35 is connected to an axle 38 which mounts the pulley 5, while the other end thereof has a hole 39 to pass a screw 40. The lever 35 is turned through the agency of the screw 40 pivotallysecured to the stop 34, and nuts 41 located on said screw 40. When the nuts 41 are moved along the screw 40 in that or this direction, the lever 35 is turned to raise or lower the pulley '5. In the above arrangement the stop 34 is given a possibility for setting displacement along the beam 32 to ensure the required tensioning of the core on the pulleys which is effected by means of the screw 42 with a handle 43 and a clamp 44.,

To limit the displacement of the driven pulley 5 (FIG. 1) with the pneumatic cylinder 30 in operation, the guide member 2 carries a straightedge 45 and a stop 46 installed with a possibility for setting displacement along the straightedge 45 depending on the length of i the cores being tensioned on the pulleys 4 and 5. The

stop 46 is essentially similar to the stop 34 and its displacement along the straightedge 35 is effected essentially similarly to that of the stop 34 along the beam 32.

The turning lever 36 of the pulley 5 is made as a yoke mounted on an axle 47 (FIG. 5 affixed to a bracket 48.

Mounted 'at one end of the lever 36 is a bearing housing 49 with an axle 50 passing therethrough. The axle 50 carries the driving pulley 4. The other end of the lever 36 has a hole for an axle 51 housed therein. The latter axle has a hole toaccommodate a screw 52 (FIG.

' The screw 52 is pivotally mounted on the bracket 48 and connected to the axle 51 by nuts 53 (FIG. 5). When the nuts 53 are moved along the screw 52, the lever 36 is turned and either raises or lowers the pulley 4.

Apart from the pulley 4, the axle 50 carries a gear 54 meshing a gear 55 which is mounted on an axle 56 of a worm wheel of a reduction unit 57.

The gear 55 is mounted coaxially to-the axle 47 which allows the gear 54 to run around the gear 55 when the lever 36 is turned.

The machine is driven from an electric motor 58 (FIG. 1) connected via a belt drive 59 to a friction clutch 60 which simultaneously takes the function of a driven pulley in the belt drive 59. The friction clutch 60 is installed on a shaft 61 connected to an integral shaft and worm 62 (FIG. 5) of the reduction unit 57 by means of a brake pulley 63 also functioning as a coupling. The worm 62 is connected by a coupling 64 to the shaft-gear l6 meshing idle gears (FIG. 2) which transmit rotation to the gear 9. Due to this connecting arrangement, the rotation speed of the gear 9 is synchronized with that of the driving pulley 4, whereas during a single revolution of the gear 9 the driving pulley 4 moves a core through a pitch value equal to the perimeter of a turned core.

At the place where the holder 11 (FIG. 7) is secured to the gear 9, the latter carries a flexible arm 65 whose free end is bent off and adapted to effect permanent The arm 65 is intended to create constant tension in a loose half of the tape resulted from applying a first layer of a wrapping material 66 to a core as the other half of this tape is applied to a core which is already increased in its perimeter by one layer of cloth in case a core is being wrapped in two layers.

For operation on a semi-automatic cycle the machine is provided with two pneumatic cylinders 67 (FIG. 5) used for engaging the friction clutch 60'and releasing the brake pulley 63, also a meter 68 (FIG. 1) to automatically stop the machine after a core makes a full revolution on the pulleys 5 and 4. Through a gear train 69 (FIG. 2) themeter is connected to the idle gears 15.

The proposed machine for wrapping, say, V-belt cores operates as follows.

The driving pulley 4 (FIG. 1) and the driven pulley 5, carriage 8, stops 34 and 46, reel 12 wound with wrapping material 66 are installed in accordance with a cross-sectional profile and length of a core 70 to be wrapped so that the neutral axis of the core coincides with the axis of rotation of the gear 9, whereby the slot 10 (FIG. 2) of the gear 9 aligns with the cut 14 in the axle 13 of the carriage 8. The meter 68 (FIG. l) is preset for the required number of revolutions depending on the cross-sectional profile and the length of thecore with regard to the rotation speed of the gear 9.

The core 70 is slipped onto the pulleys 4 and 5, whereby one of the core branches is inserted through the slot 10 and the cut 14 (FIG. 2) into the hollow of the axle 13 and also into the opening 19 of the mechanism for centering the core to the axis of the rotatable gear 9. One of the rollers 18 must be raised to the upper position to effect the above actions.

Now by turning a valve handle (not shown) air is admitted to the pneumatic cylinder 30 (FIG. 1) whose piston when forced by the air moves the beam 32 and the pulley 5 connected thereto which results in tension ing the core 70 on the pulleys 5 and 4. Then the ends of thetape 66 are fixed on the core 70 at an angle of 45 to the neutral axis thereof.

The electric motor 58 is started by pressing the START button, then another button is pressed to actuate a solenoid valve v7ll (FIG. 5) which simultaneously releases the brake pulley 63 and engages the friction clutch 60. This brings into effect the simultaneous rotation of the pulleys 4 and 5 with the core 70 and the gear 9 with the holder 11 of the reel 12 around the core 70.

To wind the core 70 with the tape material 66 at a constant pressure the holder 11 (FIG. 7) is fitted with a catch 72 to lock the reel and a braking device 73 to vary the tensioning of tape material 66 when the latter is winding off the reel 12.

In the course of moving the core 70 through a wrapping pitch value equal to the perimeter thereof, the reel 12 with the cloth makes one revolution around the core resulting in the core 70 being wrapped over a length equal to a pitch value with a number of wrapping layers depending on the width of the tape 66. In multi-layer wrapping, the tape 66 is under the effect of pressure ex erted by the flexible arm 65 which tensions the loose half of the tape width applied to the core in a first layer.

Due to the fact that the carriage 8 (FIG. 1) is spaced from the driving pulley 4 at a distance depending on the length and the cross-sectional profile of the core to be wrapped, the wrapping section of the core is always found in the determined position, wherein its rigidity is increased. The latter circumstance prevents the wrapping material 66 kept under a certain tension from displacing the core during the circular wrapping motion around said core. This eliminates folds or displaced laps in the course of core wrapping.

Upon performing a single revolution, the core 70 is stopped by a signal sent from the meter 68 and the brake 63 instantly stops the gear 9 in a position wherein the slot 10 coincides with the cut 14 in the hollow axle 13 while the friction clutch 60 is also immediately released, whereas the electric motor 58 can be either switched on or off. After the core 70 has come to a standstill, the tape of wrapping material 66 should be cut off, tensioning of the core 70 should be released by turning the valve handle and the core removed from the pulleys 4 and 5. To repeat the operating cycle a new core should be placed on and tensioned, the tape affixed and the solenoid valve actuated.

What is claimed is:

l. A machine for wrapping continuous cores in tape material, said machine comprising:

a bedframe;

a driving pulley mounted on said bedframe and a driven pulley mounted on said bedframe, said pulleys adapted to move a core; a mechanism adapted to move said driven pulley for tensioning said core; and

a mechanism for spiral-pattem wrapping of said core in tape material comprising a rotatable gear having a radial slot; a holder for a reel of the tape material being secured to the end face of said gear at an angle to the axis of rotation of said gear; a carriage mounted on said bedframe; means for setting displacements of said carriage along said bedframe in relation to the said driving pulley so as to allow continuous cores of different cross-sectional shapes and lengths to be wrapped; a hollow axle affixed to said carriage for mounting said rotatable gear thereon, the interior of said axle accomodating one of the branches of said core tensioned on said pulleys, said hollow axle having longitudinal cut for coinciding with said radial slot of said gear when one of the branches of said core is inserted through both said slot and said out into said hollow axle; a mechanism for centering said core about the axis of rotation of said gear during wrapping said core which is mounted on said hollow axle of said carriage and is disposed between said driving pulley and said carriage; at least one pair of idle gears adapted to drive said rotatable gear and disposed so that the distance between the points of tangency of their pitch circles exceeds the length of arc of said slot of said rotatable gear; and a flexible arm cantilever-mounted on said holder and adapted to be in permanent contact with the tape material unwinding off said reel.

2. A machine as claimed in claim 1, wherein said mechanism for centering said core to the axis of rotation of said rotatable gear during wrapping said core, which is mounted on said hollow axle of said carriage, comprises two pairs of rollers installed pair-wise in the horizontal and vertical planes close to each other, said rollers within each pair being spaced apart so that the combination of said two pairs of rollers forms an opening whose geometrical dimensions correspond to the cross-sectional shape of said core wrapped in the tape material, one of the vertical rollers being adapted for displacement in the vertical plane so as to accomodate in said opening one of the branches of said core tensioned by said pulleys.

3. A machine as claimed in claim 2, wherein said driven and said driving pulleys are equipped with turning levers which move the pulleys in the vertical plane for centering the core to the axis of said rotatable gear during wrapping differently profiled cores.

4. A machine as claimed in claim 1, wherein the rotation speeds of said gear and said driving pulley are synchronized and during a single revolution of said gear, said driving pulley moves the core through a pitch value equal to the perimeter of the core being wrapped. 

1. A machine for wrapping continuous cores in tape material, said machine comprising: a bedframe; a driving pulley mounted on said bedframe and a driven pulley mounted on said bedframe, said pulleys adapted to move a core; a mechanism adapted to move said driven pulley for tensioning said core; and a mechanism for spiral-pattern wrapping of said core in tape material comprising a rotatable gear having a radial slot; a holder for a reel of the tape material being secured to the end face of said gear at an angle to the axis of rotation of said gear; a carriage mounted on said bedframe; means for setting displacements of said carriage along said bedframe in relation to the said driving pulley so as to allow continuous cores of different cross-sectional shapes and lengths to be wrapped; a hollow axle affixed to said carriage for mounting said rotatable gear thereon, the interior of said axle accomodating one of the branches of said core tensioned on said pulleys, said hollow axle having longitudinal cut for coinciding with said radial slot of said gear when one of the branches of said core is inserted through both said slot and said cut into said hollow axle; a meChanism for centering said core about the axis of rotation of said gear during wrapping said core which is mounted on said hollow axle of said carriage and is disposed between said driving pulley and said carriage; at least one pair of idle gears adapted to drive said rotatable gear and disposed so that the distance between the points of tangency of their pitch circles exceeds the length of arc of said slot of said rotatable gear; and a flexible arm cantilever-mounted on said holder and adapted to be in permanent contact with the tape material unwinding off said reel.
 2. A machine as claimed in claim 1, wherein said mechanism for centering said core to the axis of rotation of said rotatable gear during wrapping said core, which is mounted on said hollow axle of said carriage, comprises two pairs of rollers installed pair-wise in the horizontal and vertical planes close to each other, said rollers within each pair being spaced apart so that the combination of said two pairs of rollers forms an opening whose geometrical dimensions correspond to the cross-sectional shape of said core wrapped in the tape material, one of the vertical rollers being adapted for displacement in the vertical plane so as to accomodate in said opening one of the branches of said core tensioned by said pulleys.
 3. A machine as claimed in claim 2, wherein said driven and said driving pulleys are equipped with turning levers which move the pulleys in the vertical plane for centering the core to the axis of said rotatable gear during wrapping differently profiled cores.
 4. A machine as claimed in claim 1, wherein the rotation speeds of said gear and said driving pulley are synchronized and during a single revolution of said gear, said driving pulley moves the core through a pitch value equal to the perimeter of the core being wrapped. 